We are regular travelers - probably a little younger than you (in our mid-50s). My husband still works and some of our travel has been me tagging along on work trips. I'm semi retired and own my own business - with a laptop and internet, can do my job in a few hours a week whenever I want. We only do a DVC trip every other year - and it will be six years between WDW trips (HHI and Aulani in between).
Washington DC is completely worth a few days if you like museum hopping So is Boston. So is San Francisco or New Orleans.
If you've never been to the Grand Canyon it is amazing.
We've used our DVC points to snowbird in HHI, and like that a lot.
We are Minnesotans and I should put in a plug for the local and wonderful North Shore of Lake Superior. If you like waterfalls and trails and sitting around looking at a body of water with no opposite shore (its COLD though), its beautiful.
My husband and/or I have been to - in the last five years - London (several times, its a favorite, and he has a conference there, so its airfare and extending the hotel room), Sydney Australia, Amsterdam, Tanzania (if you have a chance to go on safari - do it!), Taiwan, Korea, Hong Kong, Mexico. Peru is scheduled for Fall and Hawaii for next Winter. India is up soonish as well - and I want to get to Vienna and Prague.
Tours are nice as you age, you get to be in a bubble not unlike the Disney bubble. That was how we did Tanzania and how we will do Peru. I've also done the British Isles and Germany that way. Luggage is handled for you. London can be easy to do by yourself, but its Disney World levels of walking and insider knowledge - once you figure it out its easy. Until then you are standing next to a tube station trying to figure out which line you need to get on and where you need to transfer to go anywhere.